The Mudgee Line

A blog on my layout based on the Mudgee Line of the NSWGR sometime in the late 50's early 60's and also the 70's, basically between Wallerawang and Gulgong/Dunedoo in HO scale, and maybe some other modelling contents.

Friday, April 20, 2018

Ok,
Having covered the 40 & 82 in the previous post, I'll now cover the Austrains 41 and Auscision 43, so lets jump right in.

But first, a word from our sponsors ...

Wiring Info

Before I start, for those that are interested, I thought I
might outline my, ummm, 'thought process' in trying to figure out what
the PCB 'wiring' diagram is so that I can figure out what to cut and what to solder to get the result I'm after , and seeing the 43 requires modification to
only one lightboard I'll use that one as the example, so here goes a
brief explanation - but be aware there are probably better ways, this is
just my way, and for those not interested then just skip to the next
section.

I start by taking a couple of photos under a light, and if needed move the PCB to get the reflection of the traces, I can then enlarge these photos as needed to see quite clearly the components and traces/tracks on the lightboard. I then draw an outline of the PCB board and then draw the various components (LEDs & Resistors) onto it, then I draw on the traces. If the
PCB has been painted (some are, some aren't) which can make the traces difficult to see, then to enable to see the traces on the PCB I
generally move the PCB under a light to see the reflection of the light
on the trace, the 2 photos below are a couple of examples of the light
reflecting off the board and thus making the traces a little more visible.

And
the below is a couple of sketches of the lightboard with the traces
drawn onto a piece of paper, drawing on both sides, kind of like
superimposing one surface onto the other, I generally lay the paper on say a computer screen so I can see what's been drawn on one side and then draw over the top so both sides line up - I use a pencil for this step so as to not put too much pressure and damage the computer screen. One side has the LEDS, the
other the Resistors, these drawings also show the 2 plated through holes
(A & B) and the traces I cut - please note that the right hand side drawing has been flipped so that it is in the same orientation as the left hand drawing.

Using these photos and the diagrams I then try to figure out what power
is fed to where and from what feed wire, so using the Red LED as an
example, the power comes in via the Brown wire on the Bottom Right Pad
in the drawing on the Left Hand Side, travels via a trace to a resistor,
from the resistor it goes to the plated through hole 'A' to the other
side of the board (the Right Hand side drawing) and travels via another
trace to the Red LED, from there the feed goes via another trace which joins the Red and white Marker LEDs and then a trace to the Pad (which
is cut, as indicated by the red line, as part of the modification) and
exits via the (original) yellow wire on the Bottom Left Hand Pad in the
drawing on the Right Hand Side, pretty simple really :-)

Austrains 41
Only because 41 comes before 43.

First thing is to remove the body from the chassis, this done by simply removing the 2 screws near the fuel tank, and then the body simply slides off the chassis, there is no need to remove the couplers.

Bogies - I did not rewire as I thought the wiring looked OK - I did not think the wires to the bogies looked to thick & was fairly flexible.

Unmodified chassis

Light boards - these are at either end of the chassis and I think have to be retained because the springs make contact with the light boards on the round silver pads to provide power to the headlight. They also need to be modified so the white markers can work independently to the headlights, so lets see what needs to be modified.

As mentioned there are 2 main boards on the chassis, one board has the DCC 8 pin plug, the other end just has the light connections, both boards need to be modified, the round silver pads are the pads that the springs in the body make contact with to provide power to the headlights.

The modifications consist of basically cutting traces and soldering wires to the traces.

Board 1
I'll start with the easiest board to modify which is the board that does not have the 8 pin plug. This is simply a matter of cutting the trace as shown in the below photo of the underside of the board and soldering a wire as shown in the below photos

Underside of lightboard showing trace and soldered wire

Underside of lightboard with cuts and soldered wire marked

The soldered wire goes to one of the DCC decoder's function output (its the green wire soldered to Pin 3 in the photo below) and controls the white marker well, thats that board covered - pretty simple really - unfortunately the other board is a bit more involved.

Board 2

As can be seen by the above photo, to modify this board requires soldering 4 wires, as well as cutting 3 traces, they are better shown in the below photo.

Though the cuts can be in undertaken in any order, I've numbered the cuts 1 to 3 for clarity

Cut # 1 is next to the resistor marked R3, the cut is made on the trace between the resistor and the plated through hole that feeds power to the headlight pad on the top of the board, this cut will isolate the feed between the headlight and the white marker lights, The headlight gets its feed from the Pin 2, and the white markers get their power from the brown wire soldered to the base of resistor R3 (making sure you do not solder the cut trace back together), this wire is then connected to one of the decoder's functions outputs (F1 to F4)

Cut # 2 is made to the trace that comes from pin 6, this feeds the Red markers on this board and the headlight in the board (previously modified) at the other end of the model. Solder a wire (Pink in the above photo) to the base of resistor R2 (or to the cut trace as I've done), this wire is then connected to one of the decoder's functions outputs (F1 to F4) and provides power to the Red markers.

Cut # 3 is on the trace that come from Pin 2 of the 8
pin DCC plug and isolates the trace going back to the
interboard connector, it can probably be cut closer to where it joins
onto Pin 2, to the isolated section of this trace is soldered the
purple/violet wire which is then connected to one of the decoder's functions outputs (F1 to F4) and will power the Red markers in the other end of the model.

The next step is to solder the wire that was soldered to Board No. 1 ( the green wire in the first photo) to Pin No. 3, this will provide power to the White Markers in the other end of the model.

I've also drilled a couple of holes (about 2mm or so) as indicated in the board, these are used to feed the wires that have been soldered to the board from one side to the other, be careful when drilling these holes that you don't drill through the traces.

Speakers - now a decision has to be made as to what one want to do with the speaker, as I see it there are 3 options

keep the existing speaker

replace the speaker in the same location

replace the speaker in a different location - probably under the roof

Existing speaker removed from the fuel tank and a sugarcube speaker trial fitted

I thought the existing speaker was a bit low on volume , so I chose to replace the speaker in the existing location, bit of work but I'm happy with the end result. The main modification needed is to increase the space for the speaker in the existing speaker space in the fuel tank, I used a milling bit in my dremel at low speed to gently ease out the existing space into more or less a rectangular shape to suit the sugarcube speaker, I made many light passes and checked the outcome frequently until I was happy with the result that the sugarcube speaker fitted and that the fuel tank enclosure closed properly. You can either use the wires that the existing speaker uses or solder your own wires. I did not use an enclosure as the fuel tank was not closing properly because there was not enough room with the enclosure fitted , but I did manage to glue a piece of 20th (0.5mm) styrene to the face of the speaker which basically does the same job.

That just about covers the 41 class, all that remains is to re-assemble the model and enjoy.

And a couple of photos to finish with showing the end result.

Headlight Only

White Makers Only

Headlight and White Markers

Red Markers Only

Auscision 43

OK, So now that's done lets get onto modifying the 43 to make the lights work independently.
Whilst the 43 class is somewhat simpler than the 41, it still requires for some delicate soldering.

The first thing I did was to disconnect the wires that come from the
light switches in the fuel tank as I think they are not needed for DCC.

The rear marker lights need little work as the Red & White markers are individually wired and its simply a matter of connecting the right wire to the right decoder point, ie. each LED has both a Positive and a Negative wire, on my model the LEDs are wired as follows :

For the White LED the White wire is the negative and the yellow wire is the positive ground

For the Red LED the Brown wire is the negative and the Blue wire is the positive common

So simply connect the negative wires to the respective decoder function output and the positives to the decoder function common (blue wire).

The front lights on the other hand need a bit of work, not as much as the 41, but still some work to do.

The main work on the front lights occurs in the front headlight board and is mainly just a matter of un-soldering and then re-soldering a couple of wires and cutting some traces.
The first thing to do is to remove the headlight enclosure from the chassis, this is achieved by simply using a small screw driver between the enclosure and the chassis to prise the enclosure away from the chassis mine came away fairly easily, then remove the PCB/Lightboard from the enclosure, mine was held together by a couple of spots of glue. This will expose the lightboard to enable it to be worked on.

You will have noticed that there are 4 wires to the light board, for my model the original wiring layout was :

the Blue wire was the positive for the Red LED & the top White LED,

the Brown wire was the negative for Red LED,

the White wire was the negative for both White LEDs

the Yellow wire was the positive to the bottom White LED.

Whilst this setup does work, it is not very conducive to independent control of the lights via DCC, thus I have re-wired as below.

I'll start with the back of the light board first, this is the side that has the resistor (not the LEDs), the first step is to cut the trace between the 2 resistors on the left hand side of the board as indicated in the photo below and then remove & re-solder the Yellow as shown with the wire soldered to the solder pad AND the resistor (this is done because we cut the trace from this Pad to the joined Red & White LEDs it originally went to), this will provide the negative feed to the bottom White headlight LED (the lower of the 2 Yellow coloured LEDs) . The Blue wire is soldered to the pad above the Pad the Yellow wire is soldered to.

Rear of Lightboard

Front of Lightboard

The front of the lightboard contains the LEDs, they are grouped as the Red markers LED (the clear white looking LED in the top in the right hand side above photo) then the White markers LED in the middle and the Headlight LED below that (ie.the 2 Yellow coloured LEDs).

The first thing is to cut the trace between the pad the Yellow wire is soldered to and the middle LED then, using a thin piece of wire, solder a link between the 2 Yellow LEDs, this forms the common positive connection between the 3 LEDs, the top 2 LEDs have a trace joining them and the link joins them to the bottom LED, which is connected via a trace from the Pad the blue wire is soldered to. When soldering the link wire make sure you do not short it out against the plated through hole below the lower White(Yellow) LED (its the negative feed to the bottom White LED (the headlight LED) which comes from the Yellow wire which was previously soldered to the resistor).

When testing the lights I had a fair bit of light bleed through from the markers to the headlight, and whilst not very prototypical I must admit that when the Red markers were turned on I did like the dim RED headlights - kinda looked wicked, not very real, but wicked.

Those wicked looking Red headlights

To alleviate the light bleed through I glued a small piece of alfoil in the headlight enclosure between the hole for the headlight and the markers, this was cut long enough to just touch the lightboard thus blocking out the light between the headlight & markers, making sure it did not short anything out.

Alfoil strip glued to the light enclosure

There is also a piece of black tape??, behind the clear headlight pipes/casting which I think helps to stop any lightbleed through, I lost this in my model so I simply replaced it with another piece of alfoil - this seems to work OK, though if the headlight is not removed then it should not be an issue.

The rest off the install was a fairly standard job, a couple of things to note though.
I did not use a 21 pin decoder, mainly because I had a 'normal' decoder handy
Firstly I used the existing Auscision electrical board as a base to put the DCC decoder onto. I stripped the Auscision board of all it's electrical components, including the 21 pin plug but did not interfere with the traces running from one end to the other so I could use them for the common positive and the track left & right between the 2 ends.
I installed a platform above the front bogie made from some scrap 20th styrene for the capacitor to attach to
I used an iPhone 6 speaker to see what it sounded like, and whilst I do like it, I think the sound is not really any different to the sound from the sugarcube speakers used in the 40, 41 & 82 installations described previously.

DCC Decoder etc in Auscision 43 class

I think that just about covers it, and for me it gives me what I'm after.

Saturday, April 7, 2018

Those that know me know that I have a fascination with lights, be they the city lights (especially when seen from a plane) fireworks etc, or in a model, so since the last post and my daughter's wedding (see last post) I've had a bit of fun with fitting independently controlled marker lights, so I thought I'd write a small post or 2 on how I setup the marker lights to work independently to the headlights for a few different models.

The models in question are the, the Eureka 40, Austrains 41, Auscision 43 and the On Track 82.

It all started with a mate, Craig Hill, who split the headlight from the white marker lights in the Eureka 40 and showed me what he did to achieve that which gave me the inspiration to have a go, so the 40 class is the first one I'll start with, and bar the 82 is probably the easiest to achieve so lets start with that one.

The Eureka 40 Class

The first thing changed is the wiring to the bogies, a mate (Peter Baron) mentioned that he replaced the wire to the bogies of his 40 class as he thought they where a bit thick & stiff and seemed to affect the swing of the bogies, Peter did say that once he changed the bogie wiring that the model seemed to track better, good enough for me and its simply a matter of carefully using a soldering iron and removing the existing wire and soldering in the new thinner, more flexible wire.

new thinner wires in place and old thicker replaced wires in view, the difference in size is pretty obvious

The Eureka 40 has the lights controlled by 3 wires going to the light boards at either end, it's a (relatively) simple matter of cutting one of the traces on the light board(s) that connects the white marker lights to the headlight, thus isolating the head light from the white marker lights and soldering an extra wire to power the now isolated Headlight.

First up is a photo of the unmodified lightboard from both the front and the rear, the modification is fairly simple and is outlined in the following set of photos.

Front view of unmodified lightboard

Rear view of lightboard, not particularly impressed with the colour code of the wiring

The first two photos above show an unmodified lightboard, the trace that needs to be cut is on the front of the lightboard between 'P6' and LED 'L3' and the extra wire is fed through the hole above LED 'L3' and soldered to the cut trace feeding LED 'L3'

Rear Of lightboard showing new wire (white)

Where the new wire is soldered to the front of the lightboard

The 2 photos above show the modified lightboard and show the soldered extra wire on the front and the 4 wires from the rear with where the extra wire goes through the existing hole in the lightboard, I've also changed the wire colours to better meet the DCC 'standards', so the Blue wire is the common, the white is the new wire for the headlight, and the green & purple/violet wires are for the red & white markers

Rear of 40 Cl Lightboard showing
where extra wire feeds through

40 Cl Lighboard showing trace to cut and where extra wire to be soldered

The final set of 40 class lightboard photos above have drawn on them the trace that has been cut and where the extra wire is fed through and soldered onto the front of the lightboard.

Another thing that I 'improved' on the Eureka model is that there are no reflectors behind the headlights which to me looks weird, I experimented with silver paint, chrome paint (and as a side point I found a chrome paint pen name 'Matlow' which I think is brilliant) and alfoil and settled on the alfoil as it pretty well looks the part. The alfoil came from the inside of a coffee container as its a slightly thicker material than the normal store bought alfoil, I drilled a hole (about 1 - 2 mm) and then used the domed end of a knife holder to slightly dome out the alfoil to give the shape I was after. A couple of photos of the headlight show the various methods considered.

Painted reflector

Standard Headlight - no Reflector

Alfoil reflector

formed alfoil reflector

alfoil reflector and forming tool

I also found out that the marker light suffer from light bleedthrough where the light that lights the markers bleed through the body and marker light casting, this is visible in the below photo - not a very clear photo as it was taken in low light but it does show the light bleeding through.

Light bleed through at marker lights

I addressed this by painting the inside of the body around the marker lights in black paint followed by a coat of silver paint, this is shown in the below photo along with the alfoil reflector, or at least a test version of it

this along with a couple of coats of a red/brown mix on the marker lights themselves seems to have solved that little issue as evidenced by the photo below in similar light conditions were the bleedthrough is a lot less evident.

Light bleed through minimised at marker lights

So the end result is a 40class that is a lot more to my liking, the markers work independently to the headlights and the headlights have reflectors behind them.

No lights showing reflector behind the headlight

Headlight on

White Markers Only

Red Markers Only-note slight red in headlight

A couple of other things I tackled whilst working on the 40 was to install sand pipes to the bogies which are simply some .5mm brass wire bent to shape and glued in place into holes drilled into the chassis and fixing the buffers where the spring clip holding the buffer shank in place of which one was nowhere to be seen by replacing said lost spring clip with a thin piece of wire soldered to the shank, the photos below probably explain it a lot better than I can type it.

using a piece of paper as a barrier to stop the solder from going where it shouldn't when soldering the thin wire to the buffer shank

the wire soldered to the buffer shank before cleaning it up

test fitting of the sugarcube speaker

I used a sugar cube speaker and have glued it to the existing speaker tower as indicated in the above photo where I was testing for any interference to the bogie movement, pleased to say all worked well, but the speaker is glued to the speaker support over the bogie near the radiator, not the cab bogie where this photo is.

side on photo showing the sand pipes

For those with an eye to detail may notice that the model sits slightly lower than a normal Eureka 40, this is courtesy of Craig who milled out the chassis for me, something which I think is well worth doing.

And now I only have to worry about weathering to finish it off.

The On Track 82 Class

As mentioned at the beginning of this post the On Track 82 is, I think, the easiest of the 4 to separate the headlights from the markers, and if wanted to it looks like one can easily control the ditch lights separately also. This is because the lights have their own wires from the main board to the lights / lightboard and so it's simply a matter of connecting the appropriate wire to their respective output on the decoder, no need to cut wires or traces.

My On Track 82 has a Loksound v4 decoder loaded with the appropriate sounds. Most who have used the loksound decoders know, that in the main, they only have 4 amplified functions and the remainder are non-amplified low power logic level functions that do not have enough power to drive LEDs thus I've used some MOSFETs as power amplifiers to boost the output of the F3 & F4 logic function logic, not my idea - there is data on the web (as an example This UK Website discusses MOSFETs, there are others) that explains things better than I can but I'll explain what I did below, one thing to be aware of is that some MOSFETs may not work (or at least did not work for me), I originally bought some N-Channel 702-7002MOSFETs but the markers were a constant dim or bright, were I wanted On or Off (ie. not On/Dim). After doing a bit more reading I bought some N-Channel SOT-23 Transistor IRLML2502 Mosfets which gave me the results I was after (ie. On/Off), I think the important thing is that the part Id. contains the letters 'IRLM' as that seems to mean they have a low draw.

As mentioned the Headlight functions, Fwd & Rvs, and Functions 1 & 2 have the capability to power LEDs without any further amplification, however Functions 3 & 4 are low power logic level outputs and do not deliver enough power to light the LEDs, I've also read that if a device (eg.LED or light globe) is connected directly to the logic level outputs that it can damage the decoder, but one can use MOSFETs to amplify the output and thus provide enough power so that the LED markers can be connected to the appropriate output.

82 with loksound 4 fitted and sugarcube speaker

The above photo is just a general overall view of the interior of the 82 with the decoder and sugar cube speaker fitted. The speaker is more or less under the exhaust grille.

Loksound 4 and sugarcube speaker

TCS 21 pin board

The above 2 photos show the Loksound 21pin decoder, and the TCS 21pin
adapter(Part No. 21-HWM-5Pack) onto which the decoder is fitted, I cut a couple of grooves in the plastic block which supports the 21pins so that the grey and orange wires have a more or less direct route out.

The photo above is of the TCS 21pin board showing both sides, the outputs for F3 & F4 are the 2
pads on the underside of TCS board(the board on the left had side), as is the ground which needs to be used to power the MOSFET (amplifiers), you may notice that there are no solder pads to solder speaker wires to, I've simply soldered them to there respective pins and run them underneath the TCS board through to the speaker as shown below, the speaker wires are the two violet wires, they are soldered to pins 9 & 10 which are next to the blanked off index pin (pin 11), but please note that the TCS board does NOT have the index pin removed and I simply cut it off, the brown wire is soldered to the pad for Aux 3, the pink wire is soldered to the pad for Aux 4 and the black wire(s) is soldered to the ground pad.

These 3 wires (ie. the Brown Aux3, Pink Aux4 & Black Ground) are then connected to the MOSFET, one MOSFET per function, and then to their respective LED.
The MOSFET has 3 connections, namely

The Gate (G) to which the wire from the decoder Auxilary Pad (Pink or Brown) is soldered to

The Source (S) to which the wire from the decoder Ground Pad (Black) is soldered to

The Drain (D) from which the wire to the LED is soldered to

hopefully the following diagram shows this better than I've described it, and is showing the top of the MOSFET.

And the below photo is the Mosfet wired up (Black wire from ground pad, Pink wire from Aux 4 and Yellow wire to marker light LED - but please note that this is looking from the bottom up rather than top down)

And the end result of this little experiment is white marker lights that are separately controlled to the headlights